Cisco ASR 1000 Configuration Guide

11-5
Cisco ASR 1000 Series Aggregation Services Routers SIP and SPA Software Configuration Guide
OL-14127-08
Chapter 11 Troubleshooting the Gigabit Ethernet SPAs
Performing Basic Interface Troubleshooting
• Verify that a hardware failure has not occurred. Observe the LEDs to confirm the failure. See the
other troubleshooting sections of this chapter, and refer to the
Cisco ASR 1000 Series Aggregation
Services Router Hardware Installation Guide. If the hardware has failed, replace the SPA as
necessary.
• Check the autonegotiation status.
Verifying the Line Protocol Is Up
In the output from the show interfaces gigabitethernet, show interfaces tengigabitethernet, or show
interfaces fastethernet command, verify that the line protocol is up. If the line protocol is down, the
line protocol software processes have determined that the line is unusable.
Perform the following corrective actions:
• Replace the cable.
• Check the local and remote interface for misconfiguration.
• Verify that a hardware failure has not occurred. Observe the LEDs to confirm the failure. See the
other troubleshooting sections of this chapter, and refer to the
Cisco ASR 1000 Series Aggregation
Services Router Hardware Installation Guide. If the hardware has failed, replace the SPA as
necessary.
Verifying the CRC Counter
In the output from the show interfaces gigabitethernet, show interfaces tengigabitethernet, or show
interfaces fastethernet command, observe the value of the CRC counter. Excessive noise will cause
high CRC errors accompanied by a low number of collisions.
Perform the following corrective actions if you encounter high CRC errors:
• Check the cables for damage.
• Verify that the correct cables are being used for the SPA interface.
Verifying the Carrier Signal
In the output from the show interfaces gigabitethernet, show interfaces tengigabitethernet, or show
interfaces fastethernet command, observe the value of the carrier signal counters. The lost carrier
counter shows the number of times that the carrier was lost during transmission. The no carrier counter
shows the number of times that the carrier was not present during transmission.
Carrier signal resets can occur when an interface is in loopback mode or shut down.
Perform the following corrective actions if you observe the carrier signal counter incrementing outside
of these conditions:
• Check the interface for a malfunction.
• Check for a cable problem.

Cisco ASR 1000 Specifications

General

Brand	Cisco
Model	ASR 1000
Category	Network Router
Language	English